This dissertation explores the relationship between quantitative phonetic measurements and listener identification of accents of English, focusing on phonetic distance and its perceptual correlates across various English accent varieties. The Levenshtein distance (LD) measure, which quantifies string similarity by calculating the minimum cost of…

Individuals differ in their ability to perceive and learn unfamiliar speech sounds, but we lack a comprehensive theoretical account that predicts individual differences in this skill. Predominant theories largely attribute difficulties of non-native speech perception to the relationships between non-native speech sounds/contrasts and…

Upon acquiring or learning another language, cross-linguistic influence (CLI) is an inevitable phenomenon with which a bilingual speaker lives. One key aspect of CLI is its bidirectionality, flowing between both the first (L1) and second languages (L2) mutually affecting each other. However, investigations of L1 CLI on L2 have dominated previous…

Scholars have extensively investigated the effectiveness of high variability phonetic training (HVPT), that is, identification and discrimination of second language speech sounds produced by multiple speakers followed by trial-by-trial feedback. Building on the notion of incidental and multimodal learning in cognitive psychology (e.g., Lim &…

Research on native Arabic speakers' perception of non-native English phonemic contrasts has manifested various conclusions. Some studies have revealed that native Arabic speakers experience difficulty in the perception of non-native English phonemic contrasts, where others have concluded that they largely do not experience such difficulty. Due to…

Previous research has shown that an increased second language (L2) vocabulary size leads to better attunement to the cues required to distinguish L2 contrastive phones. This has been the central tenet of the vocabulary-tuning model (vocab) on the basis of evidence by Japanese learners of English in Australia. We aim to test the validity of the…

Spanish native speakers are known to pronounce onset /sC/ clusters in English with a prothetic vowel, as in "esport" for sport, due to their native language phonotactic constraints. We assessed whether accurate production of e.g. "spi" instead of "espi" was related to accurate perceptual discrimination of this…

Language experience shapes infants' abilities to process speech sounds, with universal phonetic discrimination abilities narrowing in the second half of the first year. Brain measures reveal a corresponding change in neural discrimination as the infant brain becomes selectively sensitive to its native language(s). Whether and how bilingual…

While it is well established that non-native speakers differ from native speakers in their perception and/or production of Mandarin lexical tones, empirical studies focusing on non-native "learners" are still limited. The objective of this study is to add to the current understanding of lexical tone perception by comparing native…

Tonal languages differ in how they use phonetic correlates, e.g. average pitch height and pitch direction, for tonal contrasts. Thus, native speakers of a tonal language may need to adjust their attention to familiar or unfamiliar phonetic cues when perceiving non-native tones. On the other hand, speakers of a non-tonal language may need to…

The aim of this study is to investigate the effect of vowel context and language experience in the perceived similarity between L2 English fricatives and Thai sounds. The target English sounds being investigated were the sounds /v, f, w, ?, t?, s, ð, d, z, ?, t??/. These sounds were elicited from four native English speakers in words in onset…

Explicit phonetics instruction can help second language (L2) learners to moderately improve their pronunciation, but less is known about how the instruction affects learners' perception, even though there is evidence that perception and pronunciation are related. This study provided phonetics instruction to students (n = 46) studying Spanish as a…

Bilingual speakers must acquire the phonemic inventory of 2 languages and need to recognize spoken words cross-linguistically; a demanding job potentially made even more difficult due to dialectal variation, an intrinsic property of speech. The present work examines how bilinguals perceive second language (L2) accented speech and where…

This dissertation investigates the hypothesis that the more vowel-like a consonant is, the more difficult it is for listeners to classify it as geminate or singleton. A perceptual account of this observation holds that more vowel-like consonants lack clear markers to signal the beginning and ending of the consonant, so listeners don't perceive the…

This dissertation investigates how knowledge of phonological generalizations influences speech perception, with a particular focus on evidence that phonological processing is autonomous from (rather than interactive with) auditory processing. A model is proposed in which auditory cue constraints and markedness constraints interact to determine a…